Broaching attachment



May 10 1,927; c. c. HANSEN BROACHING ATTACHMENT Filed May 14, 1926 2 Sheets-Sheet 1 t? /af////// www@ W' fum l (gdestf anden. -BY v v @2Q/Tr X v' JSORNEK MalyA 10,1921. 1;62`7,737

C. C. HANSEN BROACHING A'1"I'AC1'UENTv Filed May 14f, 1926 2 She'csr-Sheet 2 l L yl? J L D i I? Jaz' E Hmumun A f: I1 *O E; l" 0J Z Z 6 7 'l 0 y i Y e 0 l e IN VENT OR' (71a '656i nder, flex @V BY y Ng@ 75@ the reason-that the broachingjitoolwill thenv noty be suticientlyt rigid: to `prevent theajdel` parturel o thet cutting z bit from:v the desired a Patented May 10, 1927.

Unirse stares PATENT orrice.

CHARLES C. HANSEN, 0F EASTON, P ENNSYLVANIA,.ASSIGNOR TO INGERSOLL-RAND COMPANY, OE JERSEY CITY, NEW JERSEY, A CORPORATION' OF NEW JERSEY.

BROACHING ATTACHMENT;

Application filed May-14,

This invention relates to rock drills,but

series of holes in line, leaving narrow walls ofrock between the. drillv holes. After the holes havel beendrilled, thezwal'ls thus formed are cut away by. of' al broaohingy tool.' In this way the rock may be cut atl a considerable saving, ofi time and material' over other well known methods.

Anotherv` methodi frequently. employed iny operations of'lthis kind, depending, ofcourse, upon the type of; material being" quarried;` is-:toi runa reamingtool" through the drill holesxto cut; triangular notches' on I opposite sidesof: the holes, suoli notches extending.

generallyxin thedirectioniof the lineA of sev-y erance. A. light. charge: off explosive ma terialis. thenl explo-deel2 in the. drilll holes and,v` the blockis thusbroken fromtheloed:alongthe desired line'withoutinjury tothe materiali, This method: is preferred by some over the former method; forA the reason-that' a, smaller amountl of. drilling is. required.` This-is due to the. fact thatf the holes' mayk be -Spa'cedfa greater distanceY apart from-eachother and" the:spacing` thereof issnot limitedby-v the distance Whichk may' be. practicably spanned byl a broaching tool.

a ycommon rock` arts I for v the reception and guidance Iof v'both' the drillsteel andthe broaohingftooli This- Alimits the; cross section of. the-broaching'tool shanktol the'sizefof the;

ractgice, however,

drill steel shank. ThisY isi-objectionable. for

the -use -of afbroachingftool' ofi' substantially tool to be'- suitably supporte d by.; a: commonr z uniform cross-section an-dzrigidity through.- out its length.

Other objects of the invention are to enabley either a brcachingv tool o1" a.: reaming Heretofore,` 1t has beencustomaryrtoi use drill front:l head and; chuck The: present invention-.aims toI overa. Ycome this objectionable-4 Afeature: and .permits- 1926. Serial No. 109,032.

attachment, andl to permit limited oscillatory'movement ofthe broaohing tool abouti itsvvlongitudinal axisv so that' the tool may readily adjustv its position with respect' to the drill holes.l

Further. objects will be in part. obvious' and in part pointed out hereinafter.

'Ilhe inventionconsists ofl the combinations of. elements vand features of constructionlsubstantiallyas hereinafter described and more particularly pointed' vout` in the appended4 claims andillustrated: in the accompanyingl drawings, inwhichl- Figure/l is an elevation of' the front. endl' ofi a: rock drillf provided I with an'- attachment constructedf in accordance with the present invention, showingthe manner in whichv af roaming" tool may be supported by the at'- tachment, A

Figure 2 is a sectional elevation taken through Figureil oni the line 2;-2 looking in the direction of the'arrows,

Figure; 3` is a transverse view taken throughy Figure 2'on the line 3-3 looking inthe direction of the arrows,

Figure. 4l is av view similar to Figurey 1 illustrating-fthe manner in which a broaohingxtool mayl be guided bythe attachment,

Figure is a sectional elevation taken throughligure lon'the line 5-5 looking-in the; direction ofthe arrows,

Figure l63 is a transverse view taken throughtFigure 5 on the' line 6+-6 looking intliev direction of thearrows, v

yFigure 7 isa plan view off av rock face intendedto illustrate the spacing of the' drill holes Aand the 'manner in whi'chtheholes are notched/by the reaining tool illustrated in Figuresly to 3 inclusive, and

Figure 8` is a view similar to vFigure 7L illustrating thespacingof the holes-when thefrnaterial visv severed by afbroacli'ing tool;

lReferringto the drawings,l the inveifition! is shown embodied in a rock drill having ar cylinder; A, onlyfthe front" end"`ofj 'which isshown.-y Within-.the cylinder A isvr al bush- 'l ingfB; which; actsas i a guide for l a hammer piston. @adapted to reciprocate therein to deliver blows-to an anvil b'lockD.

In accordance withthe present invention, anattachment'or front head' E is .supported by theracylinder A and is secured thereto in thetpresentiiinstauce by meansl ofrside bolts F which extend through lugs G and H formed on the cylinder A and the front head E respectively. The bolts F are preferably provided with springs J which serve to hold the front head E yieldably within the cylinder A. Nuts K are screwed on the ends of the bolts F to provide a seat for one end of the springs J and also serve as a AIneans for adjusting the tension of said a shoulder S which serves as a stop for a reaming tool T having a head U at its rearward end adapted to impact or rest on the shoulder S. The cheek plate P is illustrated in the drawing as being formed integrally with the extension O, however, it is to be understood that the cheek plate may be formed as a separate member, if desired, and secured to the extension O in any suitable manner. At the point of divergence of the sides Q, is formed a groove V preferably of triangular form to receive a corner of the rectangular tool T.

Suitable and convenient means are provided for securing the tool T in operative position in the attachment O. To that end a guide block 1W having lateral end walls X to abut the extension O is provided for the front head. The lateral .sides X are spaced to cooperate with the shoulders R of the cheek plate P for holding the guide block W against transverse movement with respect to the extension C). In the present instance the guide block is provided with suitable slots Y formed in the lateral walls X for the reception of eye-bolts Z pivoted in the-extension O as at and carrying at their threaded ends nuts c which may be screwed against the outer facev of the guide block W for clamping said guide block securely in position. The guide block W, like the cheek plate P, is also provided with a triangular groove V to cooperate with the groove V in the cheek plate for guiding the tool T.

In common with the cheek plate P, the guide block W is also provided with divergng faces d, thus forming a guideway e having flared sides for a urpose to be more fully described hereinafter.

From the foregoing description, it will be observed that the reaming tool T will be adequately held against rotative movement in the attachment so that the cutting point -that the sides of the f of the tool T may be readily held centrally within a drill hole g in the rock L, and the cutting edge may also be held on the desired line to form the notches j in the sides of the drill hole g.

To insert the broaching tool T in the attachment, the nuts c may be unscrewed a sufficient distance on the bolts D to permit the bolts to be swung outwardly free of the slots Y. The guide block `W may then be removed and the reaming tool may be placed in the attachment so that one of the corners of the tool may cooperate with the groove V in the cheek plate P. Thereafter the guide block W may be placed in position and the bolts Z rocked into the slots Y and the nuts c may be screwed down firmly against the side of the guide block WV. The tool will thus be held securely in position to receive the blows of the hammer piston, transmitted in this instance by the anvil block D.

In Figures 4 to 6 inclusive is illustrated the manner in which a1 iiat rectangular broaching tool ,t may be guided in the guideway e. The broaching tool here illustrated is substantially like that described in my copending application Serial No. 80,017 entitled Broaching tool, filed J anuaryy 8, 1926. The tool accordingly has an head o which may cooperate with the shoulders S on the cheek plate P and a similar shoulder p formed on the guide block W for preventing ejection of the tool lo from the attachment. It will be noted in these figures, and more particularly in Figure 6, that the intermediate portion of the guideway eis only of suilicient width to prevent tilting of the tool. It is this portion which prevents the tool from inclining from the longitudinal a'Xis of the attachment. Owing to the fact guideway e are flared, the broaching tool le is, however, permitted to oscillate somewhat abo-ut its longitudinal axis. Such oscillatory movement of the tool is permitted for the purpose of allowing the tool to adjust its position with respect ed as to prevent a slight degree of adjust-A ment, said tool, in following a perfectly straight line, may depart from the wall between the drill holes and thus merely out a slot in the rock without actually forming a passageway between the drill holes.

I claim:

l. A broaching attachment for a rock drill, comprising a front head adapted to be secured to the rock drill, an extension on the front head having laterally diverging surfaces, a guide block having laterally diverging surfaces to cooperate With the surfaces on the extension to form a gui'deWay With flaredv sides for guiding a at rectangular tool and to permit such tool to oscillate about its longitudinal axis, and means for clamping the guide block to the extension.

2. A breaching attachment for a. rock drill, comprising a front head adapted to be secured to the rock drill, an extension on the front head having laterally diverging surfaces to cooperate with the surfaces on the extension to form a1 guideway With flared sides for guiding a broaching tool and to permit such broaching tool to oscillate about its longitudinal axis, grooves in the diverging surfaces for the reception and guidance of a reaming tool, and means for clamping the guide block to the extension.

3. A broaching attachment for a rock drill, comprising a front head adapted to be secured to the rock drill, an extension on the front head having laterally diverging surfaces, a recessed guide block removably secured to the extension, said guide block having laterally diverging surfaces cooperating With the surfaces on the extension to form a guideway with flared sides for guiding a breaching tool and to permit such tool to rock about its longitudinal aXis, rectangular grooves at the apex of the diverging surfaces for the reception and guidance of a reaming tool, shoulders at the inner ends of the diverging sides to prevent ejection of the tools from the attachment, and means for securing the guide block to the front head.

In testimony whereof I have signed this specification.

CHARLES C. HANSEN. 

